1. Field of the Invention
The invention in general concerns rotating electrical machines of the polyphase type, such as motor vehicle alternators or alternator starters.
2. Description of the Related Art
Methods of this type are known in the prior art, for example through the document U.S. Pat. No. 4,864,715. In this document, each phase winding comprises several turns and the phases are placed successively on the insertion tool in the form of a receiving wheel, and then inserted into the slots of the laminations by means of a tool comprising expelling members formed to be movable radially. Insertion is carried out phase by phase.
It should be noted that the receiving wheel has a thickness substantially equal to that of the stator.
Stators formed by this method have on both sides of the laminations very tightly packed winding overhangs, offering high resistance to the circulation of air. Moreover, the winding overhangs are non-symmetrical, one of the winding overhangs having an axial height greater than that of the other winding overhang, which is also unfavorable for the circulation of air for cooling these winding overhangs.
Furthermore, the rate of filling the slots, that is to say, the ratio between the cross-section of the bare conductive wire, usually made from copper, and the complete cross-section of the slot in which there is mounted a slot isolator intervening between the edges of the slots and the wires, is higher but the forces necessary for inserting the conductive wires into the slots are very large and can, under certain conditions, prejudice the quality of the product since there are many differing interactions between the conductive wires.
More precisely, the phase inserted last must push the phases inserted previously. The forces are poorly transmitted from one phase to another.
Under certain conditions this may prejudice the quality of the product.